Methods for pressurized water quenching of rolled materials have become known since the beginning of the nineteen sixties. According to DE-PS 84 615, after the last stage of a rolling mill, a water quenching of reinforcing steel for concrete at a final temperature of approximately 1000.degree. C. of the rolled material to an equilibrium temperature of approximately 650.degree. C. is performed, whereby at the end of the cooling period, the core temperature is reduced to approximately 800.degree. C. and the peripheral temperature of the rolled material is approximately 150.degree. C. DE-AS 23 53 034 describes a similar method. However, it states that upon abrupt cooling, the core temperature after the pressurized water quenching is still at approximately 850.degree. C. DE-AS 24 39 784 discloses the cooling of ribbed reinforcing steel for concrete, which is cooled at a rate of at least 1000.degree. C./s in one stage to a peripheral temperature of 100.degree. to 300.degree. C. and subsequently tied into bundles.
DE-PS 24 26 920 and DE-PS 29 00 271 also relate to the production of reinforcing steel for concrete by means of intensive water cooling; however, neither core temperatures nor cooling rates are specified.
In the first three mentioned published patent specifications, values for the cooling forces are specified, which have been attained in the pressurized water cooling of ribbed reinforcing steel or wire for concrete.
Although the strength values obtained with the known methods of pressurized water quenching of rolled steel products are sufficient, the ductility values barely reach the minimum permissible required limit values. The present trend towards higher ductility values can no longer be met with presently known methods.